1. Field of the Invention
The present invention pertains to an attaching structure of a fan motor that cools an electronic component, a fan case therefore, and a fan unit.
2. Description of the Related Art
Recently, as high-density mounting or high-heat-generating mounting of devices of a communication apparatus is performed, it has become necessary to cool an apparatus somehow.
Generally, air is forcedly circulated in the apparatus with a fan motor to cool the apparatus.
In many cases, at least two fan motors are fixed into a common fan case and used as a fan unit. The fan unit forms a structure in which the whole fan unit is detachably attached along with the fan case.
The fan motors are attached to the fan case constituting the fan unit. Usually, in the fan motor fixing method, the fan motor is fixed to the fan case with screws, and adhesive is further applied for screws not to loosen by vibration.
In case of the high-heat-generating mounting, it is necessary to form a chamber function to exploit the fan motor. To form a chamber, a component is attached to the fan motor.
A handle is attached to a front face of the fan unit because the fan unit is detachably attached, and the handle is usually formed as a separate component.
FIG. 1 shows an example of a configuration of a conventional fan unit. The conventional fan unit has the following drawbacks because the fan unit is formed by individual functional parts:
(1) Cost is increased because the number of structure parts (such as a handle 14 and a spacer 15) is increased.
(2) A tightening part (screw 16 or nut) is required to attach the fan motor to the fan case.
(3) Due to the vibration caused by rotation of the fan motor, adhesive is needed for the screw 16 not to loosen. In this case, the number of steps for assembling a unit increases.
Thus, as the number of parts of the conventional fan unit increased, the cost and the steps for producing the fan unit also increased.
Therefore, for example, “a fixing device for a heat dissipation apparatus” disclosed in Japanese Utility Model Registration No. 3078515 and “a fan unit fixing structure” disclosed in Japanese Patent Application Laid-Open No. 2000-022375 are proposed as a technique of fixing a fan motor without tightening parts.
However, in the techniques disclosed in Japanese Utility Model Registration No. 3078515 and Japanese Patent Application Laid-Open No. 2000-022375, the fan motor may be fixed without any tightening part, but there is no suggestion of reducing the number of functional parts such as a handle and a spacer. Therefore, the techniques cannot solve the problem on the increase of the number of structure parts.
Additionally, in the structures of the techniques disclosed in Japanese Utility Model Registration No. 3078515 and Japanese Patent Application Laid-Open No. 2000-022375, although the fan motor is fixed to the fan case, the whole fan unit cannot be detachably attached along with the fan case. Therefore, the whole fan unit including the fan case is not easily detached or attached.
Thus, the conventional technique does not provide a fan motor attaching structure in which a fan motor is fixed to a fan case without tightening parts while the number of functional parts is decreased.